Dermatology Book

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Tinea Capitis

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  1. Etiology
    1. Trichophyton tonsurans (90-95% of U.S. cases)
    2. Microsporum species (fluoresce blue-green under wood's lamp)
      1. Microsporum canis
      2. Microsporum audouinii
  2. Epidemiology
    1. Most common in
      1. Children ages 4-14 years
      2. Low socioeconomic groups
    2. Contagious Spread
      1. Easily spread by fomites or hair
      2. Person to Person Spread
        1. Non-Inflammatory Tinea Capitis
        2. Black dot Ringworm
      3. Spread from cats, dogs, and soil
        1. Inflammatory Tinea Capitis
  3. Differential Diagnosis
    1. Scaling and Inflammation predominant
      1. Seborrheic Dermatitis
      2. Atopic Dermatitis
      3. Psoriasis
      4. Impetigo
      5. Cellulitis
    2. Alopecia predominant
      1. Discoid Lupus
      2. Syphilis
      3. Alopecia Areata
      4. Trichotillomania
      5. Traction Alopecia
  4. Symptoms
    1. Pruritus (especially in Inflammatory Tinea Capitis)
  5. Signs
    1. General findings
      1. Circumscribed areas of Alopecia
      2. Boggy, raised lesion
        1. Rim of erythema (variable)
        2. Fine scale
      3. Microsporum lesions fluoresce under Wood's Lamp
        1. Trichophyton (92% of cases) does not fluoresce
        2. Hence most cases of tinea capitis do not fluoresce
    2. Classic presentation strongly suggests tinea capitis
      1. Pruritus
      2. Lymphadenopathy
      3. Alopecia
      4. Scaling
      5. Hubbard (1999) Arch Pediatr Adolesc Med 153(11):1150
    3. Non-inflammatory (epidemic) Tinea Capitis
      1. Hair gray or lusterless
      2. Hair breaks above scalp
      3. Wood's Lamp: Fluorescent (Microsporum species)
    4. Inflammatory Tinea Capitis
      1. Scalp red with Pustules or kerion
        1. Psoriasis appearance, but hairs are broken off
      2. Fever
      3. Lymphadenopathy
      4. Wood's Lamp: Fluorescent (Microsporum species)
    5. Black dot Ringworm
      1. Hair breaks off at skin level
        1. Scalp studded with tiny black dots
      2. Wood's Lamp: Not Fluorescent
  6. Diagnosis: Criteria for empiric treatment
    1. Criteria: Three or more of the following present
      1. Scalp Scaling
      2. Alopecia
      3. Occipital adenopathy
      4. Scalp Pruritus
    2. Interpretation
      1. Findings highly suggestive of tinea capitis in child
      2. Test Sensitivity: 92% (but small study)
      3. Justifies empiric tinea capitis therapy
    3. References
      1. Hubbard (1999) Arch Pediatr Adolesc Med 153:1150
  7. Complications: Kerion
    1. Allergic sensitization to fungus
    2. Results in Alopecia if untreated
  8. Labs
    1. Potassium Hydroxide (KOH)
    2. Hair Fungal Culture
  9. Management
    1. General
      1. Most Antifungal Medications require lab monitoring
      2. See specific agents for details
    2. First Line: Terbinafine
      1. Adult (and child >40 kg): 250 mg PO qd
      2. Child 20-40 kg: 125 mg PO qd
      3. Child <20 kg: 67.5 mg PO qd
      4. Treat for 4 weeks for Trichophyton tonsurans
      5. Treat for 4-8 weeks for Microsporum canis
    3. Alternative Agents
      1. Fluconazole 8 mg/kg each week for 8-12 weeks
      2. Itraconazole 3-5 mg/kg/day for 4 weeks
      3. Griseofulvin
        1. Adults: 500 mg PO qd for 4-6 weeks
        2. Child: 20 mg/kg/day until Hair Growth (8 weeks)
    4. Concurrent Topical Antifungal reduces transmission
      1. Apply for 5 minutes 2-3 times each week
      2. Agents
        1. Selenium Sulfate (2.5%) or
        2. Topical Ketoconazole or
        3. Povidone iodine lotion or Shampoo
    5. Kerion
      1. Prednisone 1 mg/kg/d or
      2. Topical Triamcinolone 0.1% Cream
  10. References
    1. Gilbert (2001) Sanford Guide to Antimicrobials
    2. Andrews (2008) Am Fam Physician 77(10):1415
    3. Schwartz (2004) Lancet 364(9440):1173
    4. Nesbitt (2000) Int J Dermatol 39(4):261

Tinea Capitis (C0040250)

Definition (MSH)Ringworm of the scalp caused by species of Microsporum and Trichophyton, which may occasionally involve the eyebrows and eyelashes. (Dorland, 27th ed)
ConceptsDisease or Syndrome (T047)
MSHD014006
EnglishBlack dot ringworm, Dermatophytosis of scalp, Ringworm of the scalp, Scalp ringworm, Tinea Capitis, Tinea of scalp
Spanishserpigo del cuero cabelludo, tina de la cabeza, tina del cuero cabelludo
Parent ConceptsScalp Dermatoses (C0036271), Tinea (C0040247), Dermatophytosis (C0011636), Scalp infection (C0581339), Duplicate concept (C1274013)
SourcesCOSTAR, LCH, MSH, NDFRT, SCTSPA, SNOMEDCT
Derived from the NIH UMLS (Unified Medical Language System)



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